Over at Aeon Byte Gnostic Radio, Sean Martin is interviewed on the revised edition of his book, The Gnostics: The First Christian Heretics. Covering, among other things, Gnosticism in Islam, the interview twice talks about David Lindsay (at about the 20 minute and, more extensively, 53 minute marks), whose inclusion in The Gnostics is one of the reasons for its new edition. You can hear the show, "The Yezidis & Gnosticism in Islam: Aeon Byte Gnostic Radio", on YouTube.